1. Field of the Invention
This invention relates to a parallel transaction processing system and, in particular, to a system and a method for efficiently processing transaction data stored in a queue by having a plurality of tasks operate independently in parallel.
2. Related Art
A prior art on-line transaction processing system was so configured that it was provided with one or more queues in the system and transaction data stored in the queues were processed one after the other by a single task or multiple tasks (sequentially or independently). For example, Japanese Published Unexamined Patent Application 1-216434 discloses a multitask control system for transaction processing which, upon occurrence of a fault, is capable of automatically taking over a process running before the occurrence of the fault. This multitask control system is characterized in that a check point file is provided for check point control in addition to a terminal control table, but does not describe control of a queue. Also, a system is known in which transaction data such as transaction log stored in a queue are processed sequentially one after the other by a single task.
There was a limit in improving the number of transaction data processings per unit time in the prior art system in which transaction data were sequentially processed by a single task. While a parallel processing by multiple tasks may be considered as a technique to solve this problem, there is a problem as to how efficiently a lot of transaction data stored in a single queue could be processed.
In addition, in order to operate a prior art transaction processing system between different CECs on a sysplex, it was necessary to additionally provide a special component such as Intersystem Extended Service (XES) of MVS, for example. Further, transaction data, once stored in a queue, had to be scheduled for task processing and can not be canceled by a user in any prior art of multitask and single task.